Ferrari, in danger of losing their motor racing world titles, have threatened to protest the results of all this year's Grands Prix in a row over tyres.

The Italian team, which use Bridgestone tyres, claim rivals Williams and McLaren have been using illegal tyres supplied by French manufacturer Michelin. "There is a facility within the regulations to investigate any matter if previously unknown information becomes available," Ferrari technical director Ross Brawn told Autosport magazine. "It's not what we want but Ferrari are very angry and frustrated as it is now clear that a large number of the Michelin teams were running illegal tyres for a considerable amount of time - and we don't know for how long yet. Measurements were taken after the Hungarian race that clearly showed that there were tyres above the legal limit and we've got to see what develops because we're not happy with that situation."

The Italian marque's technical director told an interview with Gazzetta dello Sport that Michelin's tyres have been too wide and illegal for some time.

'It is not for [him] to decide the legality of Michelin's tyres,' read a statement issued by Clermont-Ferrand.

Michelin re-iterates that the governing FIA has always sanctioned the disputed tyre design 'when new' since they first appeared at Imola in 2001.

'The FIA [then] unilaterally changed the interpretation of [the rule] by stating that the front tyre tread width must now be measured before and after use.'

Michelin still feels it is not reasonable to ask for the new scrutineering methods as of the upcoming Italian Grand Prix.

'The time-scale is much too short,' the statement continues, 'but we are ready to try to conform to this new interpretation.'
The French tyre supplier says it is 'saddened' to see the 'great house' of Ferrari involved in such false accusations of illegality and cheating.

'Michelin would like to remind you that it won its first world title in 1979 with Ferrari - a team for which Michelin has always had the greatest respect.'

It said it 'reserves the right' to take legal action following the 'slanderous remarks' of the Ferrari team-member.

The FIA has recently issued a fax regarding the front tread width size of Formula One tyres. Ross Brawn, Technical Director at the Bridgestone equipped Scuderia Ferrari Marlboro team has said that Ferrari brought this matter to the FIA’s attention as a result of information given to him by Bridgestone. Could you clarify how and when this information about the contact patch size of your rival’s front tyres came to your attention?

Yes, we have had our suspicions about this matter for some time now but it was not until this information came to our notice by way of photographic evidence at the Hungarian GP, that we could take this matter any further. I know there are some sceptics about the timing. We showed these images to Ferrari and discussed the matter at length with them and I know they took very seriously the decision whether or not to contact the FIA.